1 Faculty of Biology, Medicine and Human Health, The University of Manchester, Manchester, UK; Department of Paediatric ENT, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK; Human Factors Academy, Manchester Univeristy NHS Foundation Trust, Manchester, UK. Electronic address: Jonathan.abbas@doctors.org.uk.
2 Department of Anaesthetics and Intensive Care, Manchester Univeristy NHS Foundation Trust, Manchester, UK.
3 Faculty of Biology, Medicine and Human Health, The University of Manchester, Manchester, UK; Department of Paediatric ENT, Royal Manchester Children's Hospital, Manchester University NHS Foundation Trust, Manchester, UK.
4 Faculty of Biology, Medicine and Human Health, The University of Manchester, Manchester, UK; Department of Anaesthetics and Intensive Care, Manchester Univeristy NHS Foundation Trust, Manchester, UK.